Add loader for logging in

lib/login.dart

@@ -15,11 +15,36 @@ class _LoginPageState extends State<LoginPage> {
   final serverController = TextEditingController();
   final usernameController = TextEditingController();
   final passwordController = TextEditingController();
+  bool loggingIn = false;
+  String failedMessage = '';
 
   void connectMatrix() async {
-    final provider = Provider.of<ZenithClientProvider>(context, listen: false);
+    setState(() {
+      loggingIn = true;
+    });
+
+    try {
+      final provider =
+          Provider.of<ZenithClientProvider>(context, listen: false);
       await provider.initialize(serverController.text, usernameController.text,
           passwordController.text);
+    } catch (error) {
+      print("Error signing in $error");
+      setState(() {
+        failedMessage = error.toString();
+      });
+
+      Future.delayed(const Duration(seconds: 10), () {
+        setState(() {
+          failedMessage = '';
+        });
+      });
+      return;
+    } finally {
+      setState(() {
+        loggingIn = false;
+      });
+    }
 
     final prefs = await SharedPreferences.getInstance();
     prefs.setString("homeserver", serverController.text);
@@ -40,7 +65,8 @@ class _LoginPageState extends State<LoginPage> {
 
   @override
   Widget build(BuildContext context) {
-    return Scaffold(
+    return Consumer<ZenithClientProvider>(
+      builder: (context, provider, child) => Scaffold(
         appBar: AppBar(
           backgroundColor: Theme.of(context).colorScheme.inversePrimary,
           title: const Text("Login"),
@@ -65,16 +91,22 @@ class _LoginPageState extends State<LoginPage> {
                   controller: passwordController,
                   decoration: const InputDecoration(labelText: 'Password'),
                   obscureText: true,
+                  onFieldSubmitted: (value) => connectMatrix(),
                 ),
+                Text(failedMessage,
+                    style: Theme.of(context).textTheme.headlineSmall)
               ],
             ),
           ),
         ),
-      floatingActionButton: FloatingActionButton(
+        floatingActionButton: loggingIn
+            ? const CircularProgressIndicator()
+            : FloatingActionButton(
                 onPressed: connectMatrix,
                 tooltip: 'Log in',
                 child: const Icon(Icons.login),
               ),
+      ),
     );
   }
 }